Condoms reduce transmission from males to females by 96% and females to males by 65%. I don’t know your gender (though I am assuming male). If you’ve had two new partners since the negative blot, it is possible that you contracted HSV 2 from one of them, is it not? The bigger number is not insignificant. You may well be still negative but with a number greater than 4 now, we can’t be certain.
I think it would be helpful if you printed out both the CDC guidelines about herpes testing and information from the University of Washington about the western blot for your doctor’s. They are uninformed and need updating